LMK Display Metrology Software & ADD-ONS
LMK DISPLAY RESOLUTION Pixel Crosstalk & MTFAdd-on
- Add-on package for resolution capability (sharpness) measurements.
- The LMK Display Resolution software is part of the display add-on package. It provides two algorithms that calculate resolution parameters based on high magnification measurements. It is used to characterize “loss of sharpness” or perceived resolution. It measures the resolution capability of the display, (which includes the complete light propagation through the display stack) based on the display’s input signal resolution.
- The software package consists of two algorithms: Pixel Crosstalk and Slanted Line MTF. We recommend them for different applications.
DescriptionThis add-on is part of the display package add-on. It can be ordered separately or in combination with the other display add-ons.
Slanted Line MTF
Slanted Line MTF is a fast way to measure the resolution capability of a display in a single shot as a function of all input frequencies. The method bases on the well-established slanted edge evaluation, which is used to characterize the MTF (Modulation Transfer Function) of optical elements such as lenses. During the measurement, the LMK is slightly rotated axially relative to the display. The display shows a single line or row with a width of 1 pixel or subpixel. A luminance image is captured using a High Dynamic Range measurement. After correcting for background and the impact of the MTF-calibrated LMK lens, the display MTF is obtained from the luminance image and evaluated for all frequencies below two times the display's Nyquist frequency.
The fundamentals of the evaluation algorithms are based on the publication "Line-Based Modulation Transfer Function Measurement of Pixelated Displays," by Kenichiro Masaoka.
- Suggested Applications: Direct view displays with and without additional layers (e.g. anti-glare layer, cover layers, decor elements ...)
- Sampling conditions: We recommend a sampling ratio above 10 camera pixels per display pixel. In addition the field of view of the camera should not crop the luminance profile of the slanted line
- Limitations: The algorithm should be used with care for virtual images. Here other aberrations such as distortion, can falsely affect the MTF slanted line resolution result.
High-magnification macroscopic lenses with an optical magnification between 0.5 and 2 are required for standard displaypixel sizes, e.g. in smartphones or laptop displays. For very small display pixels, such as, e.g., micro displays, microscopic lenses with a magnification between 5 and 50 are available as well. For Near-Eye-Display resolution measurements special NED lenses wiith a small field of view are recommended.